For the tasters a difficult sentence
Until the end of the 70’s the Grappa was in the overwhelming majority of cases obtained by the distillation of mixed marcs, which means coming from really different kind of grapes.
Like this on the other hand also the wine itself was often obtained by mixing different grapes which founded place in the vinyard, both white and red ones.
The marcs therefore derived from a mixture of grapes which could variate from year to year, which gave rise to the basic grappa. The only possible differentiation was the alcoholic grade, which typically was declined into the classic trittico 40-45-50. If the company had enough and proper spaces, a part of the production was put into barrels, causing like this a matured grappa version.
The development of the enology that happened in the 70's helped to find a new selection of varieties and proper clones according to the terroir and climate, improving the vinyards and the availiability of the marcs of the single-variety.
At the end of the 70's it started to spread out the obtaining grappas by specific varieties, even if these varieties had no particular aromatic notes to justify the seperated distillation.